1. Field of the Invention
This invention relates to a wood planing device for a wood planing machine, more particularly to a wood planing device with a feeding rolling member capable of rotation at two different speeds.
2. Description of the Related Art
Referring to FIG. 1, a conventional wood planing machine 10 is shown to include a mounting frame 11 with two pairs of upright posts 13 at right and left sides thereof, respectively, a worktable 111 which is mounted at a bottom of the mounting frame 11, and a support carriage 12 which is movable upwardly and downwardly relative to the worktable 111 by operating a handle 15 to rotate a threaded bolt 14. A rotatable shaft 121 is rotatably mounted on a lower end of the support carriage 12, and is driven by a motor (not shown). Feed-in and take-out rollers 122 are mounted on the lower end of the support carriage 12 in front of and behind the rotatable shaft 121, respectively. A drive transmitting mechanism (not shown) is disposed to transmit a rotational force of the rotatable shaft 121 to the rollers 122 for feeding-in and taking-out of a workpiece supported on the worktable 111.
Since the rotational speed of the rollers 122 is fixed, the workpiece is fed at a fixed speed, thereby resulting in inconvenience during a planing operation. For example, when it is desired to plane the workpiece to a smooth surface, the feeding operation of the workpiece through the rollers 122 has to be repeated many times, thereby increasing the operating cost.
The object of the present invention is to provide a wood planing device which can shift the feeding speed of a workpiece to meet planing requirements.
According to this invention, the wood planing device includes a support carriage having right and left carriage sides which are adapted to be mounted respectively on right and left sides of a mounting frame of a wood planing machine and above a worktable. The support carriage is movable in an upright direction. A rotatable shaft is mounted on the support carriage and is driven to be rotatable about a first axis in a longitudinal direction. The rotatable shaft has a driving segment and an outer surrounding coupling segment which are disposed proximate to the left and right carriage sides, respectively. A rolling member is mounted rotatably on the right and left carriage sides, and extends in the longitudinal direction to be rotatable about a second axis parallel to the first axis. A coupling sleeve surrounds the rotatable shaft and is rotatable about the first axis. The coupling sleeve has an inner surrounding coupling segment which is sleeved on the rotatable shaft, and is shiftable along the first axis between an engaging position, where the inner surrounding coupling segment engages the outer surrounding coupling segment such that the coupling sleeve is rotated by the rotatable shaft with a first rotational drive, and a disengaging position, where the inner surrounding coupling segment disengages from the outer surrounding coupling segment. A reduction gear train includes a driving gear which surrounds and which rotates with the driving segment about the first axis, and a driven gear which surrounds the first axis and which is disposed downstream of the driving gear and adjacent to the coupling sleeve to deliver a reduction drive as a result of drive transmission from the driving gear to the driven gear. A clutch member is disposed to connect the coupling sleeve and the driven gear when the coupling sleeve is in the disengaging position so as to drive the coupling sleeve to rotate about the first axis with a second rotational drive, and is disposed to disconnect the coupling sleeve and the driven gear when the coupling sleeve is in the engaging positions. A drive delivering sleeve has a spline segment which is disposed to be in spline engagement with the coupling sleeve, and a delivering segment which is disposed distal from the coupling sleeve. The drive delivering sleeve is sleeved on and is rotatable relative to the rotatable shaft about the first axis such that the first and second rotational forces are delivered through the spline segment to rotate the delivering segment about the first axis. A drive transmitting member is disposed to transmit a rotational force of the delivering segment to the rolling member. A shifting member is disposed to shift the coupling sleeve between the engaging and disengaging positions.